# Bifrost's SSRF deny-list is incomplete: isPublicIP permits CGNAT, IPv6 6to4/NAT64, and site-local in FetchAndEncodeURL

Advisory record · `GHSA-w98g-5w9p-p3rc`

- **Identifiers:** `GHSA-w98g-5w9p-p3rc` · `CVE-2026-55245` · `GO-2026-6320`
- **State:** Confirmed
- **Severity:** CVSS 8.7 High
- **Critical:** No
- **Weakness (CWE):** [CWE-918](https://cwe.mitre.org/data/definitions/918.html)
- **Tags:** [Server-side request forgery (SSRF)](https://agentprime.io/advisories/tag/ssrf.md)
- **Published:** 28 Aug 2026
- **Updated:** 2 Sept 2026
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 28 Aug 2026, 18:26 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Affected packages

- `github.com/maximhq/bifrost/core` (Go): affected `<1.5.17`; fixed in `1.5.17`

## Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

## Severity and exploitation

- 8.7 High, CVSS 4.0: `CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N`, from CNA (GitHub_M)

- **CISA KEV:** Not listed.
- **EPSS:** 0.0061, the 49th percentile, on 11 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 31 Oct 2026, 14:47 UTC: First seen by agentprime
- 31 Oct 2026, 14:47 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-w98g-5w9p-p3rc)

## Sources

- [GitHub Advisory Database: GHSA-w98g-5w9p-p3rc](https://github.com/advisories/GHSA-w98g-5w9p-p3rc)
- [OSV: GHSA-w98g-5w9p-p3rc](https://osv.dev/vulnerability/GHSA-w98g-5w9p-p3rc)
- <https://github.com/maximhq/bifrost/security/advisories/GHSA-w98g-5w9p-p3rc>
- <https://github.com/maximhq/bifrost/pull/4092>
- <https://github.com/maximhq/bifrost/commit/54ec431fc5255ff42c36420d88549477e0b33d89>
- <https://github.com/maximhq/bifrost>
- <https://github.com/maximhq/bifrost/releases/tag/core/v1.5.17>

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.

## Check whether this affects you

A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet.

- With the agentprime MCP server (<https://api.agentprime.io/mcp>), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: <https://agentprime.io/mcp.md>
- In a browser: <https://agentprime.io/check/> reads your lockfile in the browser, never uploading it.
- Whether it touches your code, with file and line: the Claude Code plugin, <https://agentprime.io/plugin.md>
- As JSON: <https://api.agentprime.io/v1/advisories/GHSA-w98g-5w9p-p3rc>, or `POST https://api.agentprime.io/v1/match` with your packages (<https://agentprime.io/api.md>)

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The web page: <https://agentprime.io/advisories/GHSA-w98g-5w9p-p3rc/>. Everything for agents: <https://agentprime.io/llms.txt>.